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Diffstat (limited to 'arch/microblaze/mm/fault.c')
-rw-r--r--arch/microblaze/mm/fault.c63
1 files changed, 33 insertions, 30 deletions
diff --git a/arch/microblaze/mm/fault.c b/arch/microblaze/mm/fault.c
index e6a810b0c7ad..d3c3c33b73a6 100644
--- a/arch/microblaze/mm/fault.c
+++ b/arch/microblaze/mm/fault.c
@@ -28,9 +28,9 @@
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
+#include <linux/perf_event.h>
#include <asm/page.h>
-#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <linux/mmu_context.h>
#include <linux/uaccess.h>
@@ -91,7 +91,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long address,
int code = SEGV_MAPERR;
int is_write = error_code & ESR_S;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
regs->ear = address;
regs->esr = error_code;
@@ -122,10 +122,12 @@ void do_page_fault(struct pt_regs *regs, unsigned long address,
if (user_mode(regs))
flags |= FAULT_FLAG_USER;
+ perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
+
/* When running in the kernel we expect faults to occur only to
* addresses in user space. All other faults represent errors in the
* kernel and should generate an OOPS. Unfortunately, in the case of an
- * erroneous fault occurring in a code path which already holds mmap_sem
+ * erroneous fault occurring in a code path which already holds mmap_lock
* we will deadlock attempting to validate the fault against the
* address space. Luckily the kernel only validly references user
* space from well defined areas of code, which are listed in the
@@ -137,12 +139,12 @@ void do_page_fault(struct pt_regs *regs, unsigned long address,
* source. If this is invalid we can skip the address space check,
* thus avoiding the deadlock.
*/
- if (unlikely(!down_read_trylock(&mm->mmap_sem))) {
+ if (unlikely(!mmap_read_trylock(mm))) {
if (kernel_mode(regs) && !search_exception_tables(regs->pc))
goto bad_area_nosemaphore;
retry:
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
}
vma = find_vma(mm, address);
@@ -190,8 +192,9 @@ retry:
&& (kernel_mode(regs) || !store_updates_sp(regs)))
goto bad_area;
}
- if (expand_stack(vma, address))
- goto bad_area;
+ vma = expand_stack(mm, address);
+ if (!vma)
+ goto bad_area_nosemaphore;
good_area:
code = SEGV_ACCERR;
@@ -215,9 +218,16 @@ good_area:
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
- fault = handle_mm_fault(vma, address, flags);
+ fault = handle_mm_fault(vma, address, flags, regs);
+
+ if (fault_signal_pending(fault, regs)) {
+ if (!user_mode(regs))
+ bad_page_fault(regs, address, SIGBUS);
+ return;
+ }
- if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
+ /* The fault is fully completed (including releasing mmap lock) */
+ if (fault & VM_FAULT_COMPLETED)
return;
if (unlikely(fault & VM_FAULT_ERROR)) {
@@ -230,26 +240,19 @@ good_area:
BUG();
}
- if (flags & FAULT_FLAG_ALLOW_RETRY) {
- if (unlikely(fault & VM_FAULT_MAJOR))
- current->maj_flt++;
- else
- current->min_flt++;
- if (fault & VM_FAULT_RETRY) {
- flags &= ~FAULT_FLAG_ALLOW_RETRY;
- flags |= FAULT_FLAG_TRIED;
-
- /*
- * No need to up_read(&mm->mmap_sem) as we would
- * have already released it in __lock_page_or_retry
- * in mm/filemap.c.
- */
-
- goto retry;
- }
+ if (fault & VM_FAULT_RETRY) {
+ flags |= FAULT_FLAG_TRIED;
+
+ /*
+ * No need to mmap_read_unlock(mm) as we would
+ * have already released it in __lock_page_or_retry
+ * in mm/filemap.c.
+ */
+
+ goto retry;
}
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
/*
* keep track of tlb+htab misses that are good addrs but
@@ -260,7 +263,7 @@ good_area:
return;
bad_area:
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
bad_area_nosemaphore:
pte_errors++;
@@ -279,7 +282,7 @@ bad_area_nosemaphore:
* us unable to handle the page fault gracefully.
*/
out_of_memory:
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
if (!user_mode(regs))
bad_page_fault(regs, address, SIGKILL);
else
@@ -287,7 +290,7 @@ out_of_memory:
return;
do_sigbus:
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
if (user_mode(regs)) {
force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address);
return;