From: Alexandre Ghiti <alex@ghiti.fr>
Date: Thu, 24 Jun 2021 12:00:40 +0000 (+0200)
Subject: riscv: Introduce set_kernel_memory helper
X-Git-Tag: microblaze-v5.15~33^2~7^2~1
X-Git-Url: http://git.monstr.eu/?p=linux-2.6-microblaze.git;a=commitdiff_plain;h=c10bc260e7c030364b5150aac7ebf048ddfb9502

riscv: Introduce set_kernel_memory helper

This helper should be used for setting permissions to the kernel
mapping as it takes pointers as arguments and then avoids explicit cast
to unsigned long needed for the set_memory_* API.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
---

diff --git a/arch/riscv/include/asm/set_memory.h b/arch/riscv/include/asm/set_memory.h
index 086f757e8ba3..135f726c4c1d 100644
--- a/arch/riscv/include/asm/set_memory.h
+++ b/arch/riscv/include/asm/set_memory.h
@@ -17,6 +17,16 @@ int set_memory_x(unsigned long addr, int numpages);
 int set_memory_nx(unsigned long addr, int numpages);
 int set_memory_rw_nx(unsigned long addr, int numpages);
 void protect_kernel_text_data(void);
+static __always_inline int set_kernel_memory(char *startp, char *endp,
+					     int (*set_memory)(unsigned long start,
+							       int num_pages))
+{
+	unsigned long start = (unsigned long)startp;
+	unsigned long end = (unsigned long)endp;
+	int num_pages = PAGE_ALIGN(end - start) >> PAGE_SHIFT;
+
+	return set_memory(start, num_pages);
+}
 #else
 static inline int set_memory_ro(unsigned long addr, int numpages) { return 0; }
 static inline int set_memory_rw(unsigned long addr, int numpages) { return 0; }
@@ -24,6 +34,12 @@ static inline int set_memory_x(unsigned long addr, int numpages) { return 0; }
 static inline int set_memory_nx(unsigned long addr, int numpages) { return 0; }
 static inline void protect_kernel_text_data(void) {}
 static inline int set_memory_rw_nx(unsigned long addr, int numpages) { return 0; }
+static inline int set_kernel_memory(char *startp, char *endp,
+				    int (*set_memory)(unsigned long start,
+						      int num_pages))
+{
+	return 0;
+}
 #endif
 
 #if defined(CONFIG_64BIT) && defined(CONFIG_STRICT_KERNEL_RWX)