[PATCH 37/64] arch/arc: use mm locking wrappers

From: Davidlohr Bueso
Date: Sun Feb 04 2018 - 20:35:05 EST


From: Davidlohr Bueso <dave@xxxxxxxxxxxx>

This becomes quite straightforward with the mmrange in place.

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---
arch/arc/kernel/troubleshoot.c | 5 +++--
arch/arc/mm/fault.c | 12 ++++++------
2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/arc/kernel/troubleshoot.c b/arch/arc/kernel/troubleshoot.c
index 6e9a0a9a6a04..7212ba466c56 100644
--- a/arch/arc/kernel/troubleshoot.c
+++ b/arch/arc/kernel/troubleshoot.c
@@ -89,11 +89,12 @@ static void show_faulting_vma(unsigned long address, char *buf)
dev_t dev = 0;
char *nm = buf;
struct mm_struct *active_mm = current->active_mm;
+ DEFINE_RANGE_LOCK_FULL(mmrange);

/* can't use print_vma_addr() yet as it doesn't check for
* non-inclusive vma
*/
- down_read(&active_mm->mmap_sem);
+ mm_read_lock(active_mm, &mmrange);
vma = find_vma(active_mm, address);

/* check against the find_vma( ) behaviour which returns the next VMA
@@ -115,7 +116,7 @@ static void show_faulting_vma(unsigned long address, char *buf)
} else
pr_info(" @No matching VMA found\n");

- up_read(&active_mm->mmap_sem);
+ mm_read_unlock(active_mm, &mmrange);
}

static void show_ecr_verbose(struct pt_regs *regs)
diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
index e423f764f159..235e89a3ed8e 100644
--- a/arch/arc/mm/fault.c
+++ b/arch/arc/mm/fault.c
@@ -100,7 +100,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
if (user_mode(regs))
flags |= FAULT_FLAG_USER;
retry:
- down_read(&mm->mmap_sem);
+ mm_read_lock(mm, &mmrange);
vma = find_vma(mm, address);
if (!vma)
goto bad_area;
@@ -143,7 +143,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
/* If Pagefault was interrupted by SIGKILL, exit page fault "early" */
if (unlikely(fatal_signal_pending(current))) {
if ((fault & VM_FAULT_ERROR) && !(fault & VM_FAULT_RETRY))
- up_read(&mm->mmap_sem);
+ mm_read_unlock(mm, &mmrange);
if (user_mode(regs))
return;
}
@@ -171,7 +171,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
}

/* Fault Handled Gracefully */
- up_read(&mm->mmap_sem);
+ mm_read_unlock(mm, &mmrange);
return;
}

@@ -190,7 +190,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
* Fix it, but check if it's kernel or user first..
*/
bad_area:
- up_read(&mm->mmap_sem);
+ mm_read_unlock(mm, &mmrange);

bad_area_nosemaphore:
/* User mode accesses just cause a SIGSEGV */
@@ -219,7 +219,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
die("Oops", regs, address);

out_of_memory:
- up_read(&mm->mmap_sem);
+ mm_read_unlock(mm, &mmrange);

if (user_mode(regs)) {
pagefault_out_of_memory();
@@ -229,7 +229,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
goto no_context;

do_sigbus:
- up_read(&mm->mmap_sem);
+ mm_read_unlock(mm, &mmrange);

if (!user_mode(regs))
goto no_context;
--
2.13.6