[RFCv1,1/6] mm: Make get_vma_name() function public

Commit Message

Pasha Tatashin Nov. 16, 2024, 5:59 p.m. UTC

Page Detective will be using get_vma_name() that is currently used by
fs/proc to show names of VMAs in /proc/<pid>/smaps for example.

Move this function to mm/vma.c, and make it accessible by modules.

Signed-off-by: Pasha Tatashin <[e-mail]>
---
 fs/proc/task_mmu.c | 61 ----------------------------------------------
 include/linux/fs.h |  3 +++
 mm/vma.c           | 60 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 61 deletions(-)

Patch

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index e52bd96137a6..b28c42b7a591 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -240,67 +240,6 @@  static int do_maps_open(struct inode *inode, struct file *file,
 				sizeof(struct proc_maps_private));
 }
 
-static void get_vma_name(struct vm_area_struct *vma,
-			 const struct path **path,
-			 const char **name,
-			 const char **name_fmt)
-{
-	struct anon_vma_name *anon_name = vma->vm_mm ? anon_vma_name(vma) : NULL;
-
-	*name = NULL;
-	*path = NULL;
-	*name_fmt = NULL;
-
-	/*
-	 * Print the dentry name for named mappings, and a
-	 * special [heap] marker for the heap:
-	 */
-	if (vma->vm_file) {
-		/*
-		 * If user named this anon shared memory via
-		 * prctl(PR_SET_VMA ..., use the provided name.
-		 */
-		if (anon_name) {
-			*name_fmt = "[anon_shmem:%s]";
-			*name = anon_name->name;
-		} else {
-			*path = file_user_path(vma->vm_file);
-		}
-		return;
-	}
-
-	if (vma->vm_ops && vma->vm_ops->name) {
-		*name = vma->vm_ops->name(vma);
-		if (*name)
-			return;
-	}
-
-	*name = arch_vma_name(vma);
-	if (*name)
-		return;
-
-	if (!vma->vm_mm) {
-		*name = "[vdso]";
-		return;
-	}
-
-	if (vma_is_initial_heap(vma)) {
-		*name = "[heap]";
-		return;
-	}
-
-	if (vma_is_initial_stack(vma)) {
-		*name = "[stack]";
-		return;
-	}
-
-	if (anon_name) {
-		*name_fmt = "[anon:%s]";
-		*name = anon_name->name;
-		return;
-	}
-}
-
 static void show_vma_header_prefix(struct seq_file *m,
 				   unsigned long start, unsigned long end,
 				   vm_flags_t flags, unsigned long long pgoff,
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 3559446279c1..a25b72397af5 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3474,6 +3474,9 @@  void setattr_copy(struct mnt_idmap *, struct inode *inode,
 
 extern int file_update_time(struct file *file);
 
+void get_vma_name(struct vm_area_struct *vma, const struct path **path,
+		  const char **name, const char **name_fmt);
+
 static inline bool vma_is_dax(const struct vm_area_struct *vma)
 {
 	return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
diff --git a/mm/vma.c b/mm/vma.c
index 7621384d64cf..1bd589fbc3c7 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -2069,3 +2069,63 @@  void mm_drop_all_locks(struct mm_struct *mm)
 
 	mutex_unlock(&mm_all_locks_mutex);
 }
+
+void get_vma_name(struct vm_area_struct *vma, const struct path **path,
+		  const char **name, const char **name_fmt)
+{
+	struct anon_vma_name *anon_name = vma->vm_mm ? anon_vma_name(vma) : NULL;
+
+	*name = NULL;
+	*path = NULL;
+	*name_fmt = NULL;
+
+	/*
+	 * Print the dentry name for named mappings, and a
+	 * special [heap] marker for the heap:
+	 */
+	if (vma->vm_file) {
+		/*
+		 * If user named this anon shared memory via
+		 * prctl(PR_SET_VMA ..., use the provided name.
+		 */
+		if (anon_name) {
+			*name_fmt = "[anon_shmem:%s]";
+			*name = anon_name->name;
+		} else {
+			*path = file_user_path(vma->vm_file);
+		}
+		return;
+	}
+
+	if (vma->vm_ops && vma->vm_ops->name) {
+		*name = vma->vm_ops->name(vma);
+		if (*name)
+			return;
+	}
+
+	*name = arch_vma_name(vma);
+	if (*name)
+		return;
+
+	if (!vma->vm_mm) {
+		*name = "[vdso]";
+		return;
+	}
+
+	if (vma_is_initial_heap(vma)) {
+		*name = "[heap]";
+		return;
+	}
+
+	if (vma_is_initial_stack(vma)) {
+		*name = "[stack]";
+		return;
+	}
+
+	if (anon_name) {
+		*name_fmt = "[anon:%s]";
+		*name = anon_name->name;
+		return;
+	}
+}
+EXPORT_SYMBOL_GPL(get_vma_name);