[PATCH] fs/proc/vmcore: hide mmap_vmcore_fault() and vmcore_mmap_ops for nommu

From: Jisheng Zhang
Date: Sat Jun 12 2021 - 09:27:23 EST


From: Jisheng Zhang <jszhang@xxxxxxxxxx>

Without CONFIG_MMU, we get a W=1 build warning:

fs/proc/vmcore.c:443:42: warning: unused variable 'vmcore_mmap_ops' [-Wunused-const-variable]
static const struct vm_operations_struct vmcore_mmap_ops = {

The vmcore_mmap_ops is only referenced from an #ifdef'ed caller, so
this uses the same #ifdef around vmcore_mmap_ops and mmap_vmcore_fault().

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
---
fs/proc/vmcore.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 9a15334da208..d902a67cc3ea 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -401,6 +401,7 @@ static ssize_t read_vmcore(struct file *file, char __user *buffer,
return __read_vmcore((__force char *) buffer, buflen, fpos, 1);
}

+#ifdef CONFIG_MMU
/*
* The vmcore fault handler uses the page cache and fills data using the
* standard __vmcore_read() function.
@@ -443,6 +444,7 @@ static vm_fault_t mmap_vmcore_fault(struct vm_fault *vmf)
static const struct vm_operations_struct vmcore_mmap_ops = {
.fault = mmap_vmcore_fault,
};
+#endif

/**
* vmcore_alloc_buf - allocate buffer in vmalloc memory
--
2.32.0