maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault

Better describe what these functions do.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 31 insertions, 30 deletions

diff --git a/mm/debug.c b/mm/debug.c
index b5b1de8c71ac..4f376514744d 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -120,9 +120,9 @@ void __dump_page(struct page *page, const char *reason)
 		 * mapping can be invalid pointer and we don't want to crash
 		 * accessing it, so probe everything depending on it carefully
 		 */
-		if (probe_kernel_read(&host, &mapping->host,
+		if (copy_from_kernel_nofault(&host, &mapping->host,
 					sizeof(struct inode *)) ||
-		    probe_kernel_read(&a_ops, &mapping->a_ops,
+		    copy_from_kernel_nofault(&a_ops, &mapping->a_ops,
 				sizeof(struct address_space_operations *))) {
 			pr_warn("failed to read mapping->host or a_ops, mapping not a valid kernel address?\n");
 			goto out_mapping;
@@ -133,7 +133,7 @@ void __dump_page(struct page *page, const char *reason)
 			goto out_mapping;
 		}
 
-		if (probe_kernel_read(&dentry_first,
+		if (copy_from_kernel_nofault(&dentry_first,
 			&host->i_dentry.first, sizeof(struct hlist_node *))) {
 			pr_warn("mapping->a_ops:%ps with invalid mapping->host inode address %px\n",
 				a_ops, host);
@@ -146,7 +146,7 @@ void __dump_page(struct page *page, const char *reason)
 		}
 
 		dentry_ptr = container_of(dentry_first, struct dentry, d_u.d_alias);
-		if (probe_kernel_read(&dentry, dentry_ptr,
+		if (copy_from_kernel_nofault(&dentry, dentry_ptr,
 							sizeof(struct dentry))) {
 			pr_warn("mapping->aops:%ps with invalid mapping->host->i_dentry.first %px\n",
 				a_ops, dentry_ptr);
diff --git a/mm/maccess.c b/mm/maccess.c
index 88845eda5047..cc5d8c6233c0 100644
--- a/mm/maccess.c
+++ b/mm/maccess.c
@@ -6,14 +6,15 @@
 #include <linux/mm.h>
 #include <linux/uaccess.h>
 
-bool __weak probe_kernel_read_allowed(const void *unsafe_src, size_t size)
+bool __weak copy_from_kernel_nofault_allowed(const void *unsafe_src,
+		size_t size)
 {
 	return true;
 }
 
 #ifdef HAVE_GET_KERNEL_NOFAULT
 
-#define probe_kernel_read_loop(dst, src, len, type, err_label)		\
+#define copy_from_kernel_nofault_loop(dst, src, len, type, err_label)	\
 	while (len >= sizeof(type)) {					\
 		__get_kernel_nofault(dst, src, type, err_label);		\
 		dst += sizeof(type);					\
@@ -21,25 +22,25 @@ bool __weak probe_kernel_read_allowed(const void *unsafe_src, size_t size)
 		len -= sizeof(type);					\
 	}
 
-long probe_kernel_read(void *dst, const void *src, size_t size)
+long copy_from_kernel_nofault(void *dst, const void *src, size_t size)
 {
-	if (!probe_kernel_read_allowed(src, size))
+	if (!copy_from_kernel_nofault_allowed(src, size))
 		return -ERANGE;
 
 	pagefault_disable();
-	probe_kernel_read_loop(dst, src, size, u64, Efault);
-	probe_kernel_read_loop(dst, src, size, u32, Efault);
-	probe_kernel_read_loop(dst, src, size, u16, Efault);
-	probe_kernel_read_loop(dst, src, size, u8, Efault);
+	copy_from_kernel_nofault_loop(dst, src, size, u64, Efault);
+	copy_from_kernel_nofault_loop(dst, src, size, u32, Efault);
+	copy_from_kernel_nofault_loop(dst, src, size, u16, Efault);
+	copy_from_kernel_nofault_loop(dst, src, size, u8, Efault);
 	pagefault_enable();
 	return 0;
 Efault:
 	pagefault_enable();
 	return -EFAULT;
 }
-EXPORT_SYMBOL_GPL(probe_kernel_read);
+EXPORT_SYMBOL_GPL(copy_from_kernel_nofault);
 
-#define probe_kernel_write_loop(dst, src, len, type, err_label)		\
+#define copy_to_kernel_nofault_loop(dst, src, len, type, err_label)	\
 	while (len >= sizeof(type)) {					\
 		__put_kernel_nofault(dst, src, type, err_label);		\
 		dst += sizeof(type);					\
@@ -47,13 +48,13 @@ EXPORT_SYMBOL_GPL(probe_kernel_read);
 		len -= sizeof(type);					\
 	}
 
-long probe_kernel_write(void *dst, const void *src, size_t size)
+long copy_to_kernel_nofault(void *dst, const void *src, size_t size)
 {
 	pagefault_disable();
-	probe_kernel_write_loop(dst, src, size, u64, Efault);
-	probe_kernel_write_loop(dst, src, size, u32, Efault);
-	probe_kernel_write_loop(dst, src, size, u16, Efault);
-	probe_kernel_write_loop(dst, src, size, u8, Efault);
+	copy_to_kernel_nofault_loop(dst, src, size, u64, Efault);
+	copy_to_kernel_nofault_loop(dst, src, size, u32, Efault);
+	copy_to_kernel_nofault_loop(dst, src, size, u16, Efault);
+	copy_to_kernel_nofault_loop(dst, src, size, u8, Efault);
 	pagefault_enable();
 	return 0;
 Efault:
@@ -67,7 +68,7 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count)
 
 	if (unlikely(count <= 0))
 		return 0;
-	if (!probe_kernel_read_allowed(unsafe_addr, count))
+	if (!copy_from_kernel_nofault_allowed(unsafe_addr, count))
 		return -ERANGE;
 
 	pagefault_disable();
@@ -87,7 +88,7 @@ Efault:
 }
 #else /* HAVE_GET_KERNEL_NOFAULT */
 /**
- * probe_kernel_read(): safely attempt to read from kernel-space
+ * copy_from_kernel_nofault(): safely attempt to read from kernel-space
  * @dst: pointer to the buffer that shall take the data
  * @src: address to read from
  * @size: size of the data chunk
@@ -98,15 +99,15 @@ Efault:
  *
  * We ensure that the copy_from_user is executed in atomic context so that
  * do_page_fault() doesn't attempt to take mmap_lock.  This makes
- * probe_kernel_read() suitable for use within regions where the caller
+ * copy_from_kernel_nofault() suitable for use within regions where the caller
  * already holds mmap_lock, or other locks which nest inside mmap_lock.
  */
-long probe_kernel_read(void *dst, const void *src, size_t size)
+long copy_from_kernel_nofault(void *dst, const void *src, size_t size)
 {
 	long ret;
 	mm_segment_t old_fs = get_fs();
 
-	if (!probe_kernel_read_allowed(src, size))
+	if (!copy_from_kernel_nofault_allowed(src, size))
 		return -ERANGE;
 
 	set_fs(KERNEL_DS);
@@ -120,10 +121,10 @@ long probe_kernel_read(void *dst, const void *src, size_t size)
 		return -EFAULT;
 	return 0;
 }
-EXPORT_SYMBOL_GPL(probe_kernel_read);
+EXPORT_SYMBOL_GPL(copy_from_kernel_nofault);
 
 /**
- * probe_kernel_write(): safely attempt to write to a location
+ * copy_to_kernel_nofault(): safely attempt to write to a location
  * @dst: address to write to
  * @src: pointer to the data that shall be written
  * @size: size of the data chunk
@@ -131,7 +132,7 @@ EXPORT_SYMBOL_GPL(probe_kernel_read);
  * Safely write to address @dst from the buffer at @src.  If a kernel fault
  * happens, handle that and return -EFAULT.
  */
-long probe_kernel_write(void *dst, const void *src, size_t size)
+long copy_to_kernel_nofault(void *dst, const void *src, size_t size)
 {
 	long ret;
 	mm_segment_t old_fs = get_fs();
@@ -174,7 +175,7 @@ long strncpy_from_kernel_nofault(char *dst, const void *unsafe_addr, long count)
 
 	if (unlikely(count <= 0))
 		return 0;
-	if (!probe_kernel_read_allowed(unsafe_addr, count))
+	if (!copy_from_kernel_nofault_allowed(unsafe_addr, count))
 		return -ERANGE;
 
 	set_fs(KERNEL_DS);
diff --git a/mm/rodata_test.c b/mm/rodata_test.c
index 5e313fa93276..2a99df7beeb3 100644
--- a/mm/rodata_test.c
+++ b/mm/rodata_test.c
@@ -25,7 +25,7 @@ void rodata_test(void)
 	}
 
 	/* test 2: write to the variable; this should fault */
-	if (!probe_kernel_write((void *)&rodata_test_data,
+	if (!copy_to_kernel_nofault((void *)&rodata_test_data,
 				(void *)&zero, sizeof(zero))) {
 		pr_err("test data was not read only\n");
 		return;
diff --git a/mm/slub.c b/mm/slub.c
index b8f798b50d44..fe81773fd97e 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -292,7 +292,7 @@ static inline void *get_freepointer_safe(struct kmem_cache *s, void *object)
 		return get_freepointer(s, object);
 
 	freepointer_addr = (unsigned long)object + s->offset;
-	probe_kernel_read(&p, (void **)freepointer_addr, sizeof(p));
+	copy_from_kernel_nofault(&p, (void **)freepointer_addr, sizeof(p));
 	return freelist_ptr(s, p, freepointer_addr);
 }